(Newser)
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The sinking of the Sewol has claimed another victim: A civilian diver who perished while searching for bodies in the sunken South Korean ferry today. The 53-year-old man lost consciousness a few minutes after diving into waters around 80 feet deep, the BBC reports. Authorities say it was the veteran diver's first dive in the Sewol. He is the first diver to die during the search and the government has now ordered health checks for all divers involved in the operation.

Not counting the diver, the death toll from the disaster now stands at 263, with 39 people still missing, reports CNN. Around 130 divers are still searching the submerged ship, where closed cabin doors blocked by debris are making it difficult to search the few rooms that have yet to be checked. Shipping documents have revealed that the doomed ferry was severely overloaded on a regular basis, and investigators today for the first time indicated that overloading was one of the causes of the tragedy—by way of the arrest of four Chonghaejin Marine Company officials, who face charges of accidental homicide, the New York Times reports. Says a prosecutor, "We are still calculating exactly how many tons of cargo the ship was carrying, but based on what we have found out so far, it’s clear that it was carrying more than allowed."